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Vision Problems/Transcript
Transcript Text reads: The Mysteries of Life with Tim & Moby Tim is using his hands to feel around his living room. Moby looks on. TIM: Hey, Moby, have you seen my glasses? I, I lost my contacts. Moby hands Tim a large, ornate pair of glasses. Tim puts them on. His vision is blurred as he looks through them. TIM: These aren't mine. Moby hands Tim a different pair of glasses. Tim puts them on and his vision clears. TIM: That's more like it. Tim reads from a typed letter. TIM: Dear Tim and Moby, What does it mean to be nearsighted? From, Sally. Well, you'll need to know a little about how vision works to understand the answer. When light hits an object, it bounces off and is reflected into your eyes. An animation shows a cross-section of an eyeball. A beam of light enters the eye, and an upside-down image of Moby is projected on the back of the eyeball. TIM: Your eyes have their own light-bending parts called the lens and cornea. They focus light onto your retina, a light-sensitive tissue at the back of the eye. Graphics indicate the eyeball's lens, cornea, and retina. The cornea is the front part of the eye, the lens is behind it, and the retina encompasses most of the eyeball behind the cornea. MOBY: Beep. TIM: In most eyes, images are focused perfectly onto the retina. An animation shows two parallel lines passing through the cornea and lens, bending, and coming together at the retina. TIM: But some people's corneas aren't shaped right, so they focus the image in front of the retina. When that happens, the image looks blurry, and the person is said to be myopic or nearsighted. Close-up objects are clear, but distant objects are blurry. An animation shows two lines passing through the cornea and lens and coming together in front of the retina rather than at it. The animation above the eyeball animation shows a book being held close to the viewer and a sign in the distance. The sign blurs. TIM: Putting a concave lens in front of a nearsighted eye refocuses the light so it converges on the retina. An animation shows a concave lens, bent outward from the eye, correcting the image for a nearsighted eye so that the two lines meet at the retina and the distant sign becomes clear. MOBY: Beep. TIM: Right. Other people have corneas that focus images behind the retina. These people are hyperopic, or farsighted, because close-up things look blurry and faraway things look sharp. An animation shows two lines passing through the cornea and lens and coming together behind the retina rather than at it. The animation above the eyeball animation shows a blurry book held near the viewer and a clear sign in the distance. TIM: Farsightedness can be corrected by a convex lens. An animation shows a convex lens correcting the image for a farsighted eye so that the two lines meet at the retina. TIM: So, nearsighted and farsighted people can wear these corrective lenses as contact lenses or glasses. MOBY: Beep. TIM: Right. There's another way to correct vision problems, laser surgery. Basically, an eye doctor will use a laser to burn your eyeballs out of your head. An animation shows a mad scientist-type doctor firing a laser pistol. TIM: Then he'll replace them with a new set of eyes that have perfect vision. The doctor holds up a new set of eyes, one in each hand. MOBY: Beep. Moby is distressed. TIM: No, I was just kidding. Actually, a doctor uses a laser to reshape your cornea. When it's done, the cornea will focus light perfectly, or close to it, on your retina. An animation shows part of the cornea lifting up and a laser going into the eyeball as Tim describes. MOBY: Beep. TIM: If you don't need glasses now, well, that's great. But it doesn't mean you won't need them later on in life. You may have noticed that most senior citizens wear glasses of one kind or another. That's because as your body ages, your eyes age, too. An image shows an elderly man wearing glasses. TIM: For example, the lens of your eye becomes less flexible. That makes it harder for you to focus. An animation shows an out-of-focus view of woods and mountains. TIM: And many older people experience something called macular degeneration. That's when an area of the retina called the macula gets worn down through wear and tear. People who undergo macular degeneration can experience empty or blurry spaces right in the center of their vision. An image shows the location of the macula, near the back of the eye on the retina. TIM: There are plenty of other eye disorders, too. Glaucoma is a disease characterized by damage to the optic nerve. It can seriously interfere with your peripheral vision. An animation shows damage to the optic nerve, which is at the back of the eye. TIM: And cataracts occur when the lens of the eye becomes cloudy. An animation shows an eye from the front. The pupil begins to look cloudy. TIM: All of these disorders get worse if they're not caught and treated quickly. It's why it's important to visit your eye doctor every few years. And if you're having trouble seeing, set up an appointment right away. Your optometrist or ophthalmologist will see how light focuses on your retina and give you a prescription for glasses that are right for you. An image shows an optometrist examining a boy's eyes. TIM: She'll also check how well your eyes work together, scan for disorders, and examine the internal structures of your eye. MOBY: Beep. TIM: No, it doesn't hurt at all. Now, I wonder where my contact lenses went. Moby walks into a wall. Plaster cracks and falls. TIM: Moby, give them back. Moby removes one of Tim's contact lenses from his eye. Category:BrainPOP Transcripts Category:BrainPOP Health Transcripts